Sandals have been around for a long time, probably since some early human decided to protect the soles of his or her feet from rough surfaces. Nevertheless, efforts to improve the sandal continue down to the present time.
A number of inventors have proposed to construct sandals by looping the retainer straps through openings and slots in the material forming the sole of the sandal. Representative examples of such sandals can be found in United Kingdom patent No. 441,651 granted Jan. 23, 1936 to the Hertfordshire Rubber Company for "IMPROVEMENTS IN OR RELATING TO BOOTS OR SHOES", United Kingdom patent No. 560,835 granted Apr. 21, 1944 to K. G. Freund for "IMPROVEMENTS IN OR RELATING TO ORTHOPAEDIC APPLIANCES", U.S. Pat. No. 4,200,997 granted May 6, 1980 to M. G. Scheinhaus et al. for "SANDAL", and United Kingdom patent application No. 2,147,792A published May 22, 1985 for S. E. Slaughter et al. for "FOOTWEAR". A significant deficiency of all of the sandals disclosed in these four patents is that they all employ substantially inelastic straps which must be adjustably buckled or otherwise adjustably fastened to fit the foot of the wearer. In efforts to reduce the discomfort likely to be experienced by a wearer of these sandals Hertfordshire, Scheinhaus et al. and Slaughter et al. all provide for relative movement between the straps and the soles of the sandals. The resulting sandals are fairly complex and expensive to produce. It is believed that none of these sandals has been particularly successful.
U.S. Pat. No. 3,063,166 granted Nov. 13, 1962 to P. Blavier for "SANDAL" recognized the problems associated with inelastic straps and proposed, among other things, that the straps be affixed to the sole of the sandal with short strips of elastic material. Blavier proposed that the real solution to the problem lay in attaching the rear ends of the straps to the sole at a single position beneath the foot and midway between the edges of the sole. Such an arrangement offers the opportunity for the wearer to experience considerable discomfort when standing on the ends of the straps.
There continued to be a need for a comfortable sandal which can be easily placed on and removed from the wearer's foot and which is inexpensive to produce.